Reading it I feel like your video on the option 42!
Also I have a question or at least my understanding. In order to connect to roof solar panels with micro inverters during no grid power avva I need AC coupling capable inverter that would mean the inverter is able to synch the two sources together. But my understanding is micro inverters need a stable power and stable frequency in order to produce power. Micro inverters do they produce their own frequency and regulate voltage or do they latch onto whatever the grid is supplying them? Also whichever is the bigger stronger source of power is going to take over to regulate frequency as in either the solar panels inverters or the 6500EX I can’t see the micro inverts being capable of generating their own frequency they are tiny things. So that means 6500EX will the only source of frequency and voltage regulation and can probably fool the micro inverters to come on and produce power. Only thing remains is what happens to power that isn’t being used to serve load or to store in a battery I.E if solar panels are producing too much power than what is needed. 6500EX as far as I’m aware cannot shift frequency in order to curtail the solar panel output this is where automation can come into picture have some kind of power monitor with a frequency generator that can take the data from either solar assistant or batteries themselves as soon as batteries are nearing full start to inject higher frequency on the system or simpler trip the breaker that’s feeding in/out to the micro inverters. Im sure it’s not good for the mocro inverters to go from producing potentially 100% power to 0 in few cycles that’s why I think frequency generator is safer bet. As long as there are no loads that are motor based on the system at the time of frequency shifting as it can damage sensitive motors.
Edit: A separate cheaper invert that can take 48v DC invert to 240V AC sync with micro inverters and then work as a chargevert while 6500EX can be kept fed from batteries to serve load.
2nd edit: found this patent that enphase operates their inverters on:
https://patents.google.com/patent/US7899632
looks like they look for phase angles if there is phase angle error within 50 micro seconds of sample it turns on a phase shift generator if another error is detected in same cycle the inverter determines an islanding conditions has occurred and proceed to shutdown the AC output.
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